Orthopedic physical therapy and athletic training may seek to reduce the amount of joint and muscle strain by countering the effects of gravity upon the body. This can be accomplished by structural supports that the user can rest against. Some suspension frames aim to lift the user, shifting the user's weight to the suspension frame and off of the ground. Suspension frames are beneficial in the case of lower body rehabilitation because of the reduction of strain on the muscles and joints of the legs.
Ambulation therapy may be desirable in the case of lower body injuries or neurological damage that compromises the patient's balance. In addition, ambulation therapy may be useful for athletic training to lower the risk of said lower body injuries. Ambulation therapy devices typically use moving treadmills in combination with a means of suspension. In order to support the full weight of a human body and include a mechanical treadmill for ambulation, these devices are typically extremely heavy and have a large footprint. As a result, they are often too large and too expensive for ordinary consumer purchase. Similarly, modest training facilities, gyms and physical therapy centers may be unable to afford existing therapy device.
Currently known ambulation therapy devices use air or harnesses for buoyancy. For instance, U.S. Pat. No. 7,341,543 to Dandy discloses an apparatus for shifting the body weight of a runner from the runner's legs to a wheeled frame using a pelvic harness that is secured to the frame with an elastic material. Another example, the AlterG® Anti-Gravity Treadmill®, suspends the user on an inflatable cushion, which the user must enter into from the top of the machine. Securing the user in these devices can be dangerous, burdensome and inefficient, and moreover, involve straps and fabric that press into parts of the body uncomfortably as the user is suspended above the ground.